Hack up release-version.sh to allow third-party deploys (1/3)

Make the batch mode flag optional since I need to lock down some
dependency versions.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Hack up release-version.sh to allow third-party deploys (2/3)

Optionally skip pushing since I don't want to actually touch the remote
master at all.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Hack up release-version.sh to allow third-party deploys (3/3)

Optionally add an altDeploymentRepository for the third-party ImageJ
repo, since I want to deploy there instead of wherever the POM says by
default (and in the case of NAR, there is actually *no*
distributionManagement).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Add release-version.sh --thirdparty=imagej

This is a shortcut for what Curtis needed to do with NAR: deploy to
the ImageJ thirdparty repository without pushing, and with fixing up
some things in non-batch mode.

Curtis promised to test this in a couple of minutes ;-)

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Merge branch 'release-version-thirdparty'

This adds support for releasing third-party artifacts to alternate
repositories, as needed by Curtis Rueden with NAR (until it goes
into Maven Central).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>